Allowlist or Denylist? — TechKnowSurge

About this interactive

Application control decides which programs are allowed to run on a machine, and it closes a gap anti-malware leaves: shadow IT, the software users install without IT's knowledge, which may be legitimate and so never flagged, yet still widens the attack surface. There are two approaches, and their names can mislead. A denylist names the applications that may not run and allows everything else, so it is the looser control: you block a few known-bad programs but the rest of the environment is free. An allowlist does the opposite: only the named, approved applications may run, and everything else is blocked by default. That makes the allowlist far stricter and more secure, because anything not on the list, including brand-new malware the organization has never seen, simply cannot execute. To sort a card, ask whether only approved apps run (allowlist) or only named apps are blocked (denylist).

What you'll learn

Distinguish an allowlist (default-deny: only approved applications run, the stricter and more secure approach) from a denylist (default-allow: only named applications blocked), and explain how application control curbs shadow IT

Aligned to

CompTIA Security+

2.5 Explain the purpose of mitigation techniques used to secure the enterprise.

Key terms

Application Control: A security mechanism that restricts which applications are permitted to execute on a system, typically using allowlists or blocklists. Application control prevents unauthorized or malicious software from running even if it reaches the endpoint.
Allow List: An application control approach that permits only explicitly approved applications to run, blocking everything else by default.
Deny List: An application control approach that blocks only explicitly named applications, permitting all others to run by default.
Shadow IT: The use of unauthorized software, systems, or services within an organization without IT department knowledge or approval. Shadow IT creates security blind spots because unmanaged assets fall outside standard patching, monitoring, and access controls.

Topics

Interactive Streak Sort

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